1. Field of the Invention
The present invention relates to an improved apparatus for effecting gas-tight communications between first and second members having bores for the passage of fluid. More particularly, the present invention relates to an improved high-temperature, low-pressure connection for affecting fluid-tight communication between such members.
2. Description of the Background
There are numerous types of apparatus such as, for example, analytical instrumentation used in laboratories, chemical and refining plants and the like, which require connection of a first member through which is transported a fluid, such as a gas, to a second member.
One exemplary example of such a connection is shown in U.S. Pat. No. 4,991,883 to R. D. Worden, which is incorporated herein by reference. The connection shown in the '883 patent provides a fluid tight connection in spite of very wide temperature changes and operation at high temperatures which subjects the mechanical components of this connection to considerable expansion and contraction. In a preferred embodiment of the invention disclosed in the '883 patent, a fused quartz spring is used as a biasing element which maintains a constant biasing force onto a sealing ferrule which seals between an inner conduit containing a fluid and an outer sealing surface to maintain the seal in the presence of wide temperature variations and/or operation at high temperatures.
On occasion, it is desirable to use a fluid carrying conduit that is undersize with respect to the sealing ferrule. While a quartz spring provides ample force to maintain sealing pressure during wide temperature variations, such a spring may not be strong enough to make an initial seal with an undersize conduit. An apparatus which would create an initial seal after which sealing could be maintained by the quartz spring would be highly beneficial.
High temperature connections are often awkward to work with largely because they are difficult to quickly adapt to standard tubing connectors. It has not been possible in the past to make a quick-lock adaptor that could be used with any standard tubing fitting because of the wide variations in temperature that these connectors experience. The wide variations in temperature and/or operations at high temperatures are likely to cause mechanical failure of connectors operating in this environment so that quick-lock adapters which could fit to standard tubing fittings have been generally unfeasible.
Consequently, a need exists for improvements in high temperature connections and/or connectors which experience wide variations temperatures. Those skilled in the art have long sought and will appreciate the novel features of the present invention which solves these problems.